﻿#define _CRT_SECURE_NO_WARNINGS 
#include"snake.h"
//设置光标位置;
void SetPos(short x, short y)
{
	COORD pos = { x,y };
	//获取标准输出句柄
	HANDLE hOutput = GetStdHandle(STD_OUTPUT_HANDLE);
	//设置光标位置
	SetConsoleCursorPosition(hOutput, pos);
}
void WelcomeToGame()
{
	SetPos(40, 15);
	printf("欢迎来到贪吃蛇小游戏");
	SetPos(40, 25);
	system("pause");
	system("cls");
	SetPos(25, 12);
	printf("用↑ . ↓ . ← . → 分别控制蛇的移动， F3为加速，F4为减速 \n");
	SetPos(25, 13);
	printf("加速将能获得更高的分数\n");
	SetPos(40, 25); 
	system("pause");
	system("cls");
}
void CreateMap()
{
	int i = 0;
	//上(0,0)-(56, 0)
	SetPos(0, 0);
	for (i = 0; i < 58; i += 2)
	{
		wprintf(L"%c", WALL);
	}
	//下(0,26)-(56, 26)
	SetPos(0, 26);
	for (i = 0; i < 58; i += 2)
	{
		wprintf(L"%c", WALL);
	}
	//左
	//x是0，y从1开始增长
	for (i = 1; i < 26; i++)
	{
		SetPos(0, i);
		wprintf(L"%c", WALL);
	}
	//x是56，y从1开始增长
	for (i = 1; i < 26; i++)
	{
		SetPos(56, i);
		wprintf(L"%c", WALL);
	}
}
void InitSnake(pSnake ps)
{
	pSnakeNode cur = NULL;
	int i = 0;
	for (int i = 0; i < 5; i++)
	{
		cur = malloc(sizeof(SnakeNode));
		assert(cur);
		cur->next = NULL;
		cur->x = POS_X + i * 2;
		cur->y = POS_Y;
		if (ps->_pSnake == NULL)
			ps->_pSnake = cur;
		else
		{
			cur->next = ps->_pSnake;
			ps->_pSnake = cur;
		}
	}
	//打印蛇身;
	cur = ps->_pSnake;
	while (cur)
	{
		SetPos(cur->x, cur->y);
		wprintf(L"%c", BODY);
		cur = cur->next;
	}
	//初始化贪吃蛇数据；
	ps->_Dir = RIGHT;
	ps->_foodWeight = 10;
	ps->_SleepTime = 200;
	ps->_Socre = 0;
	ps->_Status = OK;
}
void CreateFood(pSnake ps)
{
	int x = 0;
	int y = 0;
again:
	do 
	{
		x = rand() % 53 + 2;
		y = rand() % 25 + 1;
	} while (x % 2 != 0);
	pSnakeNode cur = ps->_pSnake;
	//判断食物位置;
	while (cur)
	{
		if (cur->x == x || cur->y == y)
			goto again;
		cur = cur->next;
	}
	//打印食物;
	pSnakeNode food = (pSnakeNode)malloc(sizeof(SnakeNode));
	assert(food);
	food->x = x;
	food->y = y;
	SetPos(food->x, food->y);
	wprintf(L"%c", FOOD);
	ps->_pFood = food;
}

//打印提⽰信息
void PrintHelpInfo()
{
	//打印提示信息
	SetPos(64, 15);
	printf("不能穿墙，不能咬到自己\n");
	SetPos(64, 16);
	printf("用↑.↓.←.→分别控制蛇的移动.");
	SetPos(64, 17);
	printf("F1 为加速，F2 为减速\n");
	SetPos(64, 18);
	printf("ESC ：退出游戏.space：暂停游戏.");
	SetPos(64, 20);
}
//暂停游戏;
void pause()
{
	while (1)
	{
		Sleep(300);
		if (KEY_PRESS(VK_SPACE))
			break;
	}
}
//pSnakeNode psn 是下⼀个节点的地址
//pSnake ps 维护蛇的指针
int NextIsFood(pSnakeNode psn, pSnake ps)
{
	return (psn->x == ps->_pFood->x) && (psn->y == ps->_pFood->y);
}
void EatFood(pSnakeNode psn, pSnake ps)
{   
	//头插;
	psn->next = ps->_pSnake;
	ps->_pSnake = psn;
	//打印蛇身;
	pSnakeNode cur = ps->_pSnake;
	while (cur)
	{
		SetPos(cur->x, cur->y);
		wprintf(L"%c", BODY);
		cur = cur->next;
	}
	ps->_Socre += ps->_foodWeight;
	free(ps->_pFood);
	CreateFood(ps);
}
void NoFood(pSnakeNode psn, pSnake ps)
{
	//头插;
	psn->next = ps->_pSnake;
	ps->_pSnake = psn;
	pSnakeNode cur = ps->_pSnake;
	//打印蛇身；
	while (cur->next->next)
	{
		SetPos(cur->x, cur->y);
		wprintf(L"%c", BODY);
		cur = cur->next;
	}
	//释放最后一个节点，并打印空格；
	SetPos(cur->next->x, cur->next->y);
	printf("  ");
	free(cur->next);
	cur->next = NULL;
}
int KillByWall(pSnake ps)
{
	if (ps->_pSnake->x == 0 || ps->_pSnake->x == 56
		|| ps->_pSnake->y == 0 || ps->_pSnake->y == 26)
	{
		ps->_Status = KILL_BY_WALL;
		return 1;
	}
	return 0;
}
int KillBySelf(pSnake ps)
{
	pSnakeNode cur = ps->_pSnake->next;
	while (cur)
	{
		if (ps->_pSnake->x == cur->x && ps->_pSnake->y == cur->y)
		{
			ps->_Status = KILL_BY_SELF;
			return 1;
		}
		cur = cur->next;
	}
	return 0;
}
void SnakeMove(pSnake ps)
{
	pSnakeNode nextNode = (pSnakeNode)malloc(sizeof(SnakeNode));
	assert(nextNode);
	switch (ps->_Dir)
	{
	case UP:
	{
		nextNode->x = ps->_pSnake->x;
		nextNode->y = ps->_pSnake->y - 1;
		break;
	}
	case DOWN:
	{
		nextNode->x = ps->_pSnake->x;
		nextNode->y = ps->_pSnake->y + 1;
		break;
	}
	case LEFT:
	{
		nextNode->x = ps->_pSnake->x-2;
		nextNode->y = ps->_pSnake->y;
		break;
	}
	case RIGHT:
	{
		nextNode->x = ps->_pSnake->x + 2;
		nextNode->y = ps->_pSnake->y;
		break;
	}
	}
	if (NextIsFood(nextNode, ps))
		EatFood(nextNode, ps);
	else
		NoFood(nextNode, ps);
	KillBySelf(ps);
	KillByWall(ps);
}
void GameStart(pSnake ps)
{
	system("mode con cols=100 lines=30");
	system("title 贪吃蛇");
	//获取标准输出句柄;
	HANDLE hOutput = GetStdHandle(STD_OUTPUT_HANDLE);
	//隐藏光标;
	CONSOLE_CURSOR_INFO CursorInfo;
	GetConsoleCursorInfo(hOutput, &CursorInfo);//获取控制台光标信息
	CursorInfo.bVisible = false; //隐藏控制台光标
	SetConsoleCursorInfo(hOutput, &CursorInfo);//设置控制台光标状态
	//打印欢迎界面
	WelcomeToGame();
	//打印地图
	CreateMap();
	//初始化蛇
	InitSnake(ps);
	//创造第一个食物
	CreateFood(ps);
}
void GameRun(pSnake ps)
{
	//打印右侧帮助信息
	PrintHelpInfo();
	do
	{
		SetPos(64, 10);
		printf("得分：%d ", ps->_Socre);
		printf("每个食物得分：%d分", ps->_foodWeight);
		if (KEY_PRESS(VK_UP) && ps->_Dir != DOWN)
		{
			ps->_Dir = UP;
		}
		else if (KEY_PRESS(VK_DOWN) && ps->_Dir != UP)
		{
			ps->_Dir = DOWN;
		}
		else if (KEY_PRESS(VK_LEFT) && ps->_Dir != RIGHT)
		{
			ps->_Dir = LEFT;
		}
		else if (KEY_PRESS(VK_RIGHT) && ps->_Dir != LEFT)
		{
			ps->_Dir = RIGHT;
		}
		else if (KEY_PRESS(VK_SPACE))
		{
			pause();
		}
		else if (KEY_PRESS(VK_ESCAPE))
		{
			ps->_Status = END_NOMAL;
			break;
		}
		else if (KEY_PRESS(VK_F3))
		{
			if (ps->_SleepTime >= 50)
			{
				ps->_SleepTime -= 30;
				ps->_foodWeight += 2;
			}
		}
		else if (KEY_PRESS(VK_F4))
		{
			if (ps->_SleepTime < 350)
			{
				ps->_SleepTime += 30;
				ps->_foodWeight -= 2;
				if (ps->_SleepTime == 350)
				{
					ps->_foodWeight = 1;
				}
			}
		}
		//蛇每次一定之间要休眠的时间，时间短，蛇移动速度就快
		Sleep(ps->_SleepTime);
		SnakeMove(ps);

	} while (ps->_Status == OK);
}
void GameEnd(pSnake ps)
{
	pSnakeNode cur = ps->_pSnake;
	switch (ps->_Status)
	{
	case END_NOMAL:
		printf("您主动退出游戏\n");
		break;
	case KILL_BY_SELF:
		printf("您撞上自己了 ,游戏结束!\n");
		break;
	case KILL_BY_WALL:
		printf("您撞墙了,游戏结束!\n");
		break;
	}
	//清除蛇身；
	while (cur)
	{
		pSnakeNode del = cur;
		cur = cur->next;
		free(del);
		del = NULL;
	}
}